Most electronic devices have a rigid housing to protect the internal electronic components. Typically, the housing has several openings for receiving a variety of electronic components used to operate the device such as, for example, a liquid crystal display (LCD) assembly. Even after these components are secured to the housing, the openings in the housing need to be properly sealed from the inside of the housing to prevent electromagnetic radiation generated by the internal electronic components of the device from exiting the housing. Excessive electromagnetic interference (EMI) is a widespread problem in many electronic devices, especially in the high speed network systems products. These electronic devices must meet very stringent emissions standards in the United States and in other foreign countries.
Shielding devices are available which can be used to reduce EMI emissions which exit through openings formed in the housing of an electronic device. Typically, these devices are metal enclosures which are secured to the back of the electronic components within the device. The disadvantage of this arrangement is that the perimeter of the metal enclosure is not in positive and continuous contact with the housing of the device, and as a result, electromagnetic radiation can leak out of the housing around the perimeter of the electronic component.
Metal enclosures have also been secured to the back surface of an electronic component where the perimeter edge of the metal enclosure contacts the housing of the device. However, if a particular device has parts which are out of tolerance, the perimeter edge of the metal enclosure may not be in positive and continuous contact with the housing which may result in excessive EMI emissions.
Flexible metallic tape has also been used to prevent electromagnetic radiation from exiting an opening formed in a housing of an electronic device. During the manufacturing process, the metallic tape is manually applied over the back of the electronic component to seal the opening. There are a number of disadvantages to using metallic tape as a shield, including the high costs associated with the manual application of the tape. Moreover, because the manufacturing process is very labor intensive and involves the manual application of the tape, it is very difficult to achieve a consistent and uniform application of the tape from one device to another.
Accordingly, it would be desirable to have an EMI shielding apparatus that overcomes the disadvantages described above and to provide a simple, and cost effective EMI shielding apparatus.